Fluid sampling device



Aug. 5, 1969 l J. A. P. DRIVET 3,459,233

FLUID SAMPLING DEVICE med May 29, 1967 5e. 1 l Hs.

United States Patent O 3,459,263 FLUID SAMPLING DEVICE .lean AugusteProsper Drivet, St.-Germainen-Laye, France, assigner to Societe Anonyme:Societe Auxiliaire des Producteurs de Petrole Flopetrol, Iaris, FranceFiled May 29, 196'7, Ser. No. 641,895 Claims priority,applicationFrance, June 9, 1966,

Im. Cl. soin 1/10 U.S. Cl. 166-165 10 Claims ABSTRACT F THE DISCLOSUREThe study of oil fields requires a precise knowledge of the fluidscontained in them. Where, in some cases, it is possible for a Wellbottom sample to be reconstituted by re-combining those phases takenfrom the surface at the separator outlet during a well test, suchtechnique necessitates important means. Moreover, where the wellpressure is only slightly higher than the fluid bubble pressure, theonly possibility of obtaining a readily utilizable sample is to take asample from the Well bottom since the well is closed and has a verysmall output.

This accounts for sampling devices having also been made for takingfiuid samples from the bottom of a deep well.

One problem to be solved in the case of such a iiuidsampling device isthe correct control of well bottom valves so as to admit the fluid to besampled into a taking chamber and subsequently to close said chamber.Another problem is to close this chamber under such conditions that thesampling device remains closed when being lifted in the wellirrespective of the ambient pressure conditions and that the contents ofsaid chamber may be verified at ground surface and transferred to abottle or any other transporting container. Known sampling devices havenot, however, permitted this problem to be satisfactorily solvedhitherto.

An object of the invention is to provide a sampling device adaptedproperly to achieve correct control of the valves in the requiredfashion `and to be kept closed when being lifted through the Wellregardless of pressure conditions.

Another object of the invention is to provide a iiuidsampling device fordeep wells adapted to be lowered into the well by means of a steel wireline and including a sampling chamber defined in the body of the deviceand delineated adjacent each end by a bore-forming seat through which anassociated valve may be tightly slidden by engagement into it, bothvalves being positively interconnected by a control rod `anddisplaceable from an opened position, particularly for allowing theiiuid to be sampled to enter said chamber and a closed position throughsaid seats, means urging said valves into said closed position, atriggering mechanism controlling the motion of said rod so as to closethe valves, and a timer which sets the instant at which said triggeringmechanism operates.

A further object of the invention is to arrange for the distance betweenthe seats and the valves to be so calculated that one of the valves canbe opened while the other valve is still closed, particularly when thesample is transferred to a new bottle or container situated on theground surface. For obtaining this result, the distance between thevalves carried by the control rod is preferably shorter than thedistance between an end of the bore forming a seat and the end of theother seat-like bore which extends in the same direction axially of thesampling device. Thus one valve can be opened inwardly of the chamberwhile the other valve is still in the corresponding seat-like bore andin closed position.

Preferably the valves are held in closed position, irrespective ofambient pressure conditions, by one or several locking members forexample of the snap-in type and/ or by a spring.

Yet another object of the invention, is to arrange for thevalve-interconnecting rod to terminate at its free end in the form of ahead or similarly outlined formation permitting axial coupling with acontrol device so as to provide, during transfer of the sample to theground surface, an accurate control of said rod for a sequentialpositive opening of the two valves.

A still further object of the invention is to provide a sampling devicein the body of which is defined a chamber so shaped adjacent each end asto permit an easy connection (for example by screwed parts) of thosedevices adapted to perform the transfer of the sample to thetransporting container and to enable control of the valveinterconnectingrod to take place.

In a suitable constructional form, the triggering mechanism includes adual screw element system one element of which is connected with a timerby which it is rotated while the other element is so urged (eithernaturally or artificially) when it is freed owing to the rotation of thefirst element in the unscrewing direction as to engage a percutor orhitting pin, a valve or an equivalent member capable of providing acommunication for achieving displacement of a piston slidable in acylinder and connected to the valve-interconnecting rod of the samplingdevice. Such a communication then displaces the piston responsive to apressure differential and consequently the actuation of thevalve-carrying rod and the closing of the valves in the medium to besampled after a period of time which is set by the timer and the screwelement system.

It will be understood that adjustment of the :screw element systempermits an easy determination of the instant when the triggering actionwill take place.

With these and such other objects in view as will incidentally `appearhereafter, the invention comprises the novel construction andcombination of parts as described in the accompanying diagrammaticexemplifying the same and forming a part of this disclosure.

FIG. l is an axial sectional view showing the triggering mechanism ofthis improved sampling device.

FIG. 2 is an axial sectional view of the body of the sampling device.

FIG. 3 is a view showing the body of the sampling device as inverted forthe transfer of the sample to a transporting container.

The triggering mechanism `shown in FIG. 1 comprises a tubular element 1constituting the body of this mechanism and closed lat its upper end bya plug 2 having a screw-threaded stem 3 adapted to receive an elementpermitting this mechanism to be connected to a steel wire line. Insidethe body 1 is housed a timer 4 of the type commonly used in theoil-exploiting industry the operating period of which may vary from 3 to180 hours. The drum shaft 5 of this timer 4 is connected to a screw 6guided by a stationary collar bearing 7 and associated 3 with a tappedweight 8 having a guiding pin 9 cooperating with a longitudinal slot 10formed in a sleeve 11 connected to the timer 4 and carrying the collarbearing 7 that guides the screw `6.

The purpose of the weight 8 is, as described hereafter, to engage bypercussion or otherwise a hitting pin or percussor 12 adapted toperforate a diaphragm 13 so as to provide a communication through anaxial passage 13a between the annular chamber 14 of the triggeringmechanism and a cylinder 15 in which is received for sliding motion apiston 16 having its lower end connected with a coupling sleeve 17provided with an innerly screw-threaded portion 18 and subjected to thepressure prevailing in the well owing to ports 19 formed at the lowerend of the tubular element 1.

The sampling device shown by FIG. 2 comprises a tubular body 20 providedat its upper end with a sleeve 21 screwed into said tubular body 20 andhaving a bore 22 forming a seat and at its lower end `a sleeve 23 havinglikewise a bore 24 forming a seat. The sleeve 21 has an extension 23fitted with a screw-thread 26 for connection with the triggeringmechanism (FIG. 1). The sleeve 23 which is screwed into the tubularelement 20 is connected with interposition of a sleeve 27 with an shoe28 for-ming the lower end portion of the sampling device and having arecess 29 housing a filter 30. Between the sleeves 21 and 23 is providedinside the tubular element 20 a chamber 31. In each seat-forming bore 22or 24 may be engaged by a fiuid tight sliding motion an associated valve32 or 33. These two valves are positively interconnected by a controlrod 34 terminating adjacent its free end by a screw-threaded stem 34aengageable into the sleeve 17 and near its opposite end by a head 35connected to it by a stern of small diameter 36.

The distance between the valves 32, 33 carried by the control rod 34 isadvantageously less than the distance between the seat-forming bore 22of the end of the other bore 24 extending in the same direction withrespect to the sampling device, whereby one 0f the valves can be openedwhile the other one is still closed.

The valves 32, 33 are preferably held in closed position (as representedin broken lines in FIG. 2) irrespective of the ambient pressureconditions by a coil spring 37 and a locking system comprising a leafspring 38 having a finger 39 abuttable, when the valves 32, 33 are inclosed position, against the upper face of the extension 25 of thesleeve 21.

The sampling operation takes place as follows:

When preparing the triggering mechanism for operation, care should betaken to engage the weight 8 only upon a length of the screw 6corresponding to the period at the end of which triggering should occur.Thus assuming a timer to have an operating period equal to t (totalnumber of revolutions of the arbor of the drum 5) care should be taken,where it .is desired to trigger the operation at a period equal to t/ 3,to engage the weight 8 only over a length equal to one third of thescrew 6. The body of the sampling device is then coupled by means of thescrew-threaded portion 26, with the triggering mechanism represented inFIG. 1, whereafter the operation of the several contrivances arecorrelated by engaging the sleeve 17 upon the screw-threaded portion 34aof the free end of rod 34 controlling the valves 32, 33, and theassembly thus made up is lowered .into the well by being suspended froma steel wire line. At this time the valves 32, 33 occupy the positionrepresented in full lines on FIG. 2.

When the assembly has reached the sampling level, it is slowly raisedand again lowered several times so as to fill up the sampling devicewith the fluid to be sampled which flows into the chamber 31 by passingthrough the filter 30. In proportion as time passes, the weight 8 goesdown and when reaching the end of the screw 6 freely slides through thesleeve 11 and ultimately engages the percutor 12 which, when perforatingthe diaphragm 13, establishes a communication between the oil filledcylin- CFI der 15 and the chamber 14 in which a pressure nearly equal toatomspheric pressure prevails.

Due to the effect of the difference of pressures, the piston 16 is movedupwardly while actuating the rod 34 carrying the valves 32, 33 `andclosing these in the medium to be sampled as represented in broken linesin FIG. 2.

The assembly of parts is then lifted to the ground surface, the shoe 28is unscrewed and the body of the sampling device is separated from thetri gering mechanism. The -body of the sampling device is afterwardsinverted (as shown in FIG. 3) and an upper transfer head 40 is adaptedto the sleeve 27, said head having lingers 41 pivotally carried by anelement 42 housed in said head and associated with a knurled nut 43. Tothe extension 25 of the sleeve 21 is also adapted a lower transfer head44 having a gate valve 45. Conditioning of the assembly made up of thesampling device and transfer heads is effected by filling the hollowportions with mercury, using therefor the gate valves 45, 46 afterhaving produced vacuum or more simply taken the precaution of nottrapping air.

For appreciating the quality of the sample, it is necessary to open thevalve 32 without opening the valve 33 so as to be able to inject throughthe lower transfer head 44 successive quantities of mercury forre-compressing the sample to the attainment of the bubble point.

Opening of the valve 32 is done by applying pressure through the lowertransfer head 44 until the head of the stem 35 abuts the support of thefingers 41. A research for the bubble point is then effected.

When the sample has been recognized as being proper, it is necessary tocompress the same before transferring it through the gate valve 46 (byresorting to usual methods as used in the oil trade) into a transportingbottle or container. Consequently the upper valve should be opened. Thisoperation is done by screwing the knurled nut 43 on its screw. Thelatter shifts the carrier for the fingers 41 which move off the conewhile permitting their retraction and are closed under the head 35. Thestem 34 is then shifted and opens the valve 33. The two valves 32, 33then occupy their initial position as shown in full lines in FIG. 2.

The opening of the valve 33 following that of the valve 32 is obtainedin this instance by means of a transfer head that has been engaged fromthe top. However on some appliances this head can be also screwed fromthe bottom upon the sampling device. In this case, this device is notinverted and assumes a transfer position similar to the one that itoccupies in the well.

Obviously the constructional details of the abovedescribed embodimentcan be altered in the field of technical equivalencies without departingfrom the scope of the invention. Thus for example the lower valve maycontain a needle valve held closed in sampling position. Following itslift up to the ground surface, when it is desired to determine thebubble point, the possibility exists of screwing upon the lower end ofthe sampling -device a transfer head permitting said needle valve to beopened from the exterior.

One may also envisage to replace the seats and valves assemblies asabove described by a device in which the valves do not move out of theirseat, ports provided in said valves permitting, depending upon theposition of the valves with respect to them, either to open or to closethe chamber.

What is claimed is:

1. A fluid-sampling device for deep wells adapted to be lowered into thewell by means of a steel wire line and comprising a body Vdefining asampling chamber having two ends, a bore-forming seat arranged adjacenteach end of said chamber, a valve slidably mounted in each seat, saidvalves being shiftable between an opened position allowing penetrationof the fluid to be sampled and a closed position in the seats, a rodinterconnecting said valves, means for urging said valves to closedposition, a triggering mechanism for controlling motion of said rod soas to close the valves, and a timer for setting the instant at whichsaid mechanism operates.

2. A duid-sampling device according to claim 1 in which the distancebetween the valve is smaller than the distance from one end of theseat-forming bore to the other bore extending in the same directionaxially of the device so that one valve may be opened while the othervalve is still closed.

3. A Huid-sampling device according to claim 1 comprising locking meansfor holding the valves in closed position.

4. A fluid-sampling device according to claim 1 in which thevalve-interconnecting rod has a free end including a head arrangedadjacent said free end of the rod, an actuator adaptable upon the bodyof the sampling device, and coupling means in said actuator forcooperating with said head so as to perform a precise control of the rodfor opening the valves when thesample is transferred from the deviceafter it has ybeen lifted up to the ground surface.

5. A Huid-sampling device for deep Wells adapted to be lowered into anoil or like well by being suspended from a steel wireline, comprising abody dening a sampling chamber and having two ends, screw-threads atboth ends of said body, screw-threaded parts engaged with them fordelineating said chamber, seat-forming bores in said parts, valvesslidably fitted in said bores and shiftable between an opened positionand a closed position in the seats, a control rod interconnecting saidvalves, said rod having a screw-threaded end and a free end, elasticmeans urging said rod towards a valve-closing position, a triggeringmehanism removably adapted upon said body, a screw-thread in saidmechanism for coupling'it with the lirst end of the rod, said mechanismbeing operable to close the valves, and a timer mounted in saidmechanism for setting the instant at which it operates.

6. A Huid-sampling device according to claim 5 comprising locking meansassociated with the rod for holding the valves in closed position.

7. A huid-sampling device according to claim 5 in which the distancebetween the valves on the rod is larger than the distance between themutually confronted ends of the screw-threaded parts but smaller thanthe distance from one end of one of these parts to the end of the othersimilarly extending part axially of the body.

8. A fluid-sampling device according to claim 5 cornprising a head atthe free end of the rod, an actuator removably adaptable to the body,and coupling means shiftable by said actuator and engageable over saidhead for shifting said rod and opening the valves.

9. A fluid samping device according to claim S comprising a shoeremovably adaptable to the device body, a bore in said shoecommunicating with the bore in the adjacent screw-threaded part, and afilter in the bore of the shoe.

10. A Huid-sampling device according to claim 5 in which the timerincludes a rotary drum, and the triggering mechanism comprises ascrew-threaded stemI conwith said drum, a weight screwed upon said stem,a guiding sleeve, said weight being slidable in said sleeve, means forangularly locking said weight, a valve in said sleeve adjacent one ofits ends for actuation by said weight, a cylinder, said valvecommunicating with said cylinder, a piston slidable through saidcylinder, a coupling member on said piston, and means on said stem forcooperating with said coupling member for interconnecting said stem andsaid piston.

References Cited UNITED STATES PATENTS 2,298,627 lO/ 1942 Proudman et al73425.4 2,342,367 2/1944 Pryor 166-165 2,577,210 12/1951 -Ruska 73-425.4X 2,613,848 10/1952 Wood 73-425.4 X 2,625,226 1/1953 Wofford 73-425.4 X2,728,397 12/1955 Ruska 166--162 X 2,870,844 1/1959 Barnes 166-165 DAVIDH. BROWN, Primary Examiner U.S. Cl. XR. 73-425

